David Hume on Causality

Hume on Causality

I realise that most people find David Hume to be a really boring read. That is somewhat true. But this doesn't mean that his ideas aren't interesting, or applicable to more recent concerns. On the contrary, his ideas are still very much influential in a number of areas of philosophy... Look at more recent attempts to surmount 'Hume's problem' (the problem of induction) for instance... So, try and enjoy this somewhat long winded writeup, if it helps, I actually find some of the stuff in here to be interesting. INTERESTING but certainly not without its gigantic problems. I'm not going to nitpickHume in this writeup too much, feel free too add writeups in that spirit though, I love me some nitpicking.

Near the beginning of his Enquiry Concerning Human UnderstandingDavid Hume states (as an illustration of the common sense view of the world) that, "nothing at first view, may seem more unbounded than the thought of man, which not only escapes all human power and authority, but is not even restrained within the limits of nature and reality" (Hume 11). And, it is true, very few people (outside of philosophical circles) would argue with this statement. Given the preponderance of fantastic literature, science and art created by humans the creative powers of the mind do seem to be unbounded by the limits of the material (empirical) world in which they exist.

Though our thought seems to possess this unbounded liberty, we shall find, upon a nearer examination, that it is really confined within very narrow limits, and that all this creative power of the mind amounts to no more than the faculty of compounding, transposing, augmenting, or diminishing the materials afforded us by the senses and experience (Hume 11).

So, within the first few sections of the work, Hume has already distanced himself (considerably) from the common sense view of the human mind. Our 'creative' powers, far from being the source of limitless freedom, are intimately and inextricably bound to the empirical world of the senses. Everything we can possibly create has/will have its origins in the sensory world.

This primary assumption (that all thoughts/ideas originate in sense 'impressions') leads to the question of how we 'create' ideas which seem to be outside the limitations of the senses. Things like golden mountains, God (the ever present 'problem' of God...) spring to mind. Hume's answer begins and ends with three principles that govern the relations between ideas:

These three functions of the mind, Hume believes, account for almost all supposedly 'creative' acts of the mind (Hume does propose one objection, that of the colour scale. I believe that this objection is easily defeated, and I will not discuss it in this writeup). In this writeup I'll chiefly deal with the last of these three principles: Cause and Effect.

Hume again challenges common sense opinion when he states that causality, far from being a 'necessary' connection between to events, is merely a habit of the mind --something we do within our mind to connect disparate events into a seamless whole. A common example used to illustrate Hume's account of causality is that of one billiard ball striking another. For Hume, there is no necessary (or direct) connection between the event of the two balls colliding and the subsequent (and separate) event of the struck ball moving off in a new direction. These two things are distinct events, which occur entirely separately. The only connection is in our minds. We connect certain events, not because of some interaction with or apprehension of the 'real' world, but because we have repeatedly experienced that when one particular event occurs, another particular event has always followed. So, for Hume if we had never seen an event similar to a billiard ball striking another, we could not extrapolate (based on either the nature of the event or the nature of the billiard-ball-in-itself) that the struck ball would move off in a new direction. There is no rational necessity between a ball being struck and it moving off in a certain direction at a certain speed.

This can be more simply and common-sensibly illustrated with the example of an unread/read book. If you are reading a book (for the first time) in which a character is about to take a drive, there is, for you, no necessary connection betweeen that drive and her death. But, if you are reading that book for the ninth time, you will necessarily connect that drive to her shooting over the edge of a cliff to her ultimate demise (what an exciting book).

The contingency of cause and effect can be made obvious, but it still seems to be a little bit of a stretch to apply it to ALL events. Hume is saying that the only difference between our expectations upon reading a book and our expectations upon witnessing a game of billiards is one of degree (not one of 'kind'). We have higher expectations from a billiard ball because this particular cause and effect 'habit' is more highly confirmed (by past experiences) than is our experience of the novel (which can be radically different from book to book). Hume argues that if we have never experienced an event of a particular kind (or one similar to it), if we are experiencing something radically new, we have no criteria upon which to predict the supposedly-causal outcome. Causality is, fundamentally, a learned behaviour of the mind, and not a fact about the world (or, if it is a fact about the world, it is one which we can never be certain about).

Hume's critique of the common sense view of causality (a common sense view that had long been one of the strongholds of rationality) leads us directly to the radical critique of reason itself, the details of why this is so I leave to the interested noder to ex-Hume. I think this early undercutting of rationality (pre-Nietzsche) as a tool of legitimation has been largely successful in defeating subsequent rationalist arguments. For pragmatic reasons (i.e.: his help in making rationality look bad, something I enjoy quite a bit) I tend to agree with Hume's somewhat simplistic account of causality. Well, perhaps 'agree' is too strong a word: I do not object vehemently to Hume's account would be more appropriate.

I think that, far from destroying society and forcing humanity to lapse into some sort of chaos (by ignoring the concept of causality altogether), Hume has simply shown that any philosophical/scientific/political system cannot/should not be grounded in the external world, or in some form of transcendental rationality that directly connects to 'reality' as such. In light of his critique we can no longer justify our beliefs.morals (whatever they may be) by appeal to the external world or rationality. The previous question, 'what can we justify these beliefs we hold?' has to be supplanted with the question, 'can anything be legitimated without an appeal to some (metaphysical) unity outside itself?'.

The almost unanimous answer to the latter question (of what can justify) before Hume's scepticism would have been that we cannot legitimate beliefs/morals without an appeal to some metaphysical unity (God, rationality, the external world, etc. etc.) After Hume, however, such legitimisation/justification became highly problematic, and the subject of intense philosophical debate that continues even today. (For a particularly in-depth example, look at the debate in epistemology between Foundationalism and Coherentism).

The important question now becomes (for me, and 'neo'-pragmatists like Richard Rorty)whether or not philosophy should even attempt to provide legitimisation. Can we live without metaphysical justification? Is it possible to accept this sceptical position and not have all social institutions and systems come tumbling down around you?

no trace of divinity remained, either in the form of a divinized world or a divinized self. Such a culture would have no room for the notion that there are nonhuman forces to which human beings should be responsible (Rorty 45).

Rorty believes that such a culture, far from being wrought by anxiety over its contingency (in its fundamental susceptibility to historical change and its self-responsibility without recourse to something outside itself) would instead

try not to wnat something which stands beyond history and institutions. The fundamental premise is that a belief can still regulate action, can still be thought worthy of dying for, among people who are quite aware that this belief is caused by nothing deeper than contingnet historical circumstance... a liberal utopia [is a] society in which the charge of 'relativism' has lost its force, one in which the notion of 'something that stands behind history' has become unintelligible, but in which a sense of human solidarity remains intact. (Rorty 189-90]

So, in Rorty's view (which can be linked closely to Hume's debunking of metaphysical appeals) the social institutions that society functions within (governments, science, etc., etc.) would not be destroyed by the radical critique of reason, they would be strengthened by the realisation (for lack of a better term) that they are fundamentally contingent. The simple realisation that we can no longer rely on anything outside ourselves to legitimate what we do and what we think does not, in itself, destroy us or society. Rather it can create a more liberal society, one that is less prone to cruelty (intellectual and otherwise) and one that does not need to decieve itself with metaphysics in order to survive. Thus, Hume's scepticism is not simply a destructive, undermining force, but can provide the realisation necessary for a more liberal community.